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      1 /*	$NetBSD: bt_close.c,v 1.17 2016/09/24 21:31:25 christos Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1990, 1993, 1994
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * This code is derived from software contributed to Berkeley by
      8  * Mike Olson.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  * 3. Neither the name of the University nor the names of its contributors
     19  *    may be used to endorse or promote products derived from this software
     20  *    without specific prior written permission.
     21  *
     22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     32  * SUCH DAMAGE.
     33  */
     34 
     35 #if HAVE_NBTOOL_CONFIG_H
     36 #include "nbtool_config.h"
     37 #endif
     38 
     39 #include <sys/cdefs.h>
     40 __RCSID("$NetBSD: bt_close.c,v 1.17 2016/09/24 21:31:25 christos Exp $");
     41 
     42 #include "namespace.h"
     43 
     44 #include <assert.h>
     45 #include <errno.h>
     46 #include <stdio.h>
     47 #include <stdlib.h>
     48 #include <string.h>
     49 #include <unistd.h>
     50 
     51 #include <db.h>
     52 #include "btree.h"
     53 
     54 static int bt_meta(BTREE *);
     55 
     56 /*
     57  * BT_CLOSE -- Close a btree.
     58  *
     59  * Parameters:
     60  *	dbp:	pointer to access method
     61  *
     62  * Returns:
     63  *	RET_ERROR, RET_SUCCESS
     64  */
     65 int
     66 __bt_close(DB *dbp)
     67 {
     68 	BTREE *t;
     69 	int fd;
     70 
     71 	t = dbp->internal;
     72 
     73 	/* Toss any page pinned across calls. */
     74 	if (t->bt_pinned != NULL) {
     75 		mpool_put(t->bt_mp, t->bt_pinned, 0);
     76 		t->bt_pinned = NULL;
     77 	}
     78 
     79 	/* Sync the tree. */
     80 	if (__bt_sync(dbp, 0) == RET_ERROR)
     81 		return (RET_ERROR);
     82 
     83 	/* Close the memory pool. */
     84 	if (mpool_close(t->bt_mp) == RET_ERROR)
     85 		return (RET_ERROR);
     86 
     87 	/* Free random memory. */
     88 	if (t->bt_cursor.key.data != NULL) {
     89 		free(t->bt_cursor.key.data);
     90 		t->bt_cursor.key.size = 0;
     91 		t->bt_cursor.key.data = NULL;
     92 	}
     93 	if (t->bt_rkey.data) {
     94 		free(t->bt_rkey.data);
     95 		t->bt_rkey.size = 0;
     96 		t->bt_rkey.data = NULL;
     97 	}
     98 	if (t->bt_rdata.data) {
     99 		free(t->bt_rdata.data);
    100 		t->bt_rdata.size = 0;
    101 		t->bt_rdata.data = NULL;
    102 	}
    103 
    104 	fd = t->bt_fd;
    105 	free(t);
    106 	free(dbp);
    107 	return (close(fd) ? RET_ERROR : RET_SUCCESS);
    108 }
    109 
    110 /*
    111  * BT_SYNC -- sync the btree to disk.
    112  *
    113  * Parameters:
    114  *	dbp:	pointer to access method
    115  *
    116  * Returns:
    117  *	RET_SUCCESS, RET_ERROR.
    118  */
    119 int
    120 __bt_sync(const DB *dbp, u_int flags)
    121 {
    122 	BTREE *t;
    123 	int status;
    124 
    125 	t = dbp->internal;
    126 
    127 	/* Toss any page pinned across calls. */
    128 	if (t->bt_pinned != NULL) {
    129 		mpool_put(t->bt_mp, t->bt_pinned, 0);
    130 		t->bt_pinned = NULL;
    131 	}
    132 
    133 	/* Sync doesn't currently take any flags. */
    134 	if (flags != 0) {
    135 		errno = EINVAL;
    136 		return (RET_ERROR);
    137 	}
    138 
    139 	if (F_ISSET(t, B_INMEM | B_RDONLY)
    140 	    || !F_ISSET(t, B_MODIFIED | B_METADIRTY))
    141 		return (RET_SUCCESS);
    142 
    143 	if (F_ISSET(t, B_METADIRTY) && bt_meta(t) == RET_ERROR)
    144 		return (RET_ERROR);
    145 
    146 	if ((status = mpool_sync(t->bt_mp)) == RET_SUCCESS)
    147 		F_CLR(t, B_MODIFIED);
    148 
    149 	return (status);
    150 }
    151 
    152 /*
    153  * BT_META -- write the tree meta data to disk.
    154  *
    155  * Parameters:
    156  *	t:	tree
    157  *
    158  * Returns:
    159  *	RET_ERROR, RET_SUCCESS
    160  */
    161 static int
    162 bt_meta(BTREE *t)
    163 {
    164 	BTMETA m;
    165 	void *p;
    166 
    167 	if ((p = mpool_get(t->bt_mp, P_META, 0)) == NULL)
    168 		return (RET_ERROR);
    169 
    170 	/* Fill in metadata. */
    171 	m.magic = BTREEMAGIC;
    172 	m.version = BTREEVERSION;
    173 	m.psize = t->bt_psize;
    174 	m.free = t->bt_free;
    175 	m.nrecs = t->bt_nrecs;
    176 	m.flags = F_ISSET(t, SAVEMETA);
    177 
    178 	memmove(p, &m, sizeof(BTMETA));
    179 	mpool_put(t->bt_mp, p, MPOOL_DIRTY);
    180 	return (RET_SUCCESS);
    181 }
    182